Disposable syringe



Dec. 6, 1949 A, E, SMITH 2,490,553'

DIsPosABLE SYRINGE Filed sept. 2o, 1947 Patented Dec. 6, 1949 UNITEDSTATES PATENT OFFICE DISPOSABLE SYRINGE Arthur E. Smith, Los Angeles,Calif.

Application September 20, 1947, Serial No. 775,194 13 claims. (c1.12s-21s) This invention relates to a disposable syringe.

The general object of the invention is to provide a syringe, preferablyadapted for single-use, and wherein a medicinal preparation, such as alocal anaesthetizing solution, may be injected.

A more specific object of the invention is to provide a novel syringe ofthe disposable type whereby a fresh solution may be prepared within thesyringe and then expelled therefrom.

A more specific object of the invention is to provide a syringeincluding a drug holding compartment and a vehicle holding compartmentand wherein the two may be brought together in a novel manner to providea fresh solution.

Another object of the invention is to provide a syringe including abarrel with a drug therein and a piston and wherein the vehicle for thedrug is carried Within the piston and wherein the vehicle is removedfrom the piston and caused to flow into the barrel to place the drug insolution when the piston is moved in one direction in the barrel.

A more specific object of the invention is to provide a syringe plungerhaving a chamber for the reception of a liquid and wherein novel meansis provided for first causing the liquid to pass from the plunger to thebarrel upon movement of the plunger in one direction relative to thebarrel and thereafter for causing the liquid to be discharged from thebarrel upon movement of the plunger in a reverse direction.

Other objects and advantages of my invention will be apparent from thefollowing description taken in connection with the accompanyingdrawings, wherein:

Fig. 1 is a side elevation of a syringe embodying the features of myinvention;

Fig. 2 is a fragmentary, central, sectional view, showing the syringe;

Fig. 3 is a central, sectional view, showing the syringe after thesolution is prepared;

Fig. 4 is a fragmentary, central, sectional view,

showing a modification of my invention;

Fig. 5. is a view similar to Fig. 4, showing a further modification, and

Fig. 6 is a fragmentary, central, sectional view, showing the manner inwhich the ball valve is moved to its seat.

Referring to the drawing by reference chai'- acters, I have shown myinvention as embodied in a syringe which is indicated generally at II).

As shown, the syringe includes a cylindrical barrel II which has aninwardly directed flange I2 at one end thereof. Within the barrel Iarrange a plunger I3. This plunger is preferably spaced from the barreland is provided with an outwardly directed flange I4, which is adjacentto the flange I2. The barrel and plunger may be made of plastic or othersuitable material.

Arranged upon the end of the plunger, is a rear end member I5, which ispreferably made of rubber and which includes an axial bore I6 whichincludes an enlarged intermediate portion I1. The portion I1 includes avalve seat i8 and spaced ribs I9. A valve ball 2l) is passed through thebore I6 by stretching the rubber as shown in Fig. 6 and when in placeserves to permit communication through the bore I6 to the interior ofthe plunger and to prevent passage from the interior of the plungeroutwardly.

The rear end member and the barrel are preferably of the same exteriordiameter and during shipment are preferably held in place by a label orseal 2 I.

The plunger has a reduced portion 22 at its forward end and on thisportion I arrange a piston 23 which includes beads 24 which engage theinner wall of the barrel I I.

The plunger is yclosed as at 25 and is provided with an axial bore 26which is enlarged intermediate its length to provide a valve seat 21,engaged by a valve ball 28, which is normally urged to its seat by aspring 29. A split ring 33, fitting in a groove 3|, serves to hold thespring in place. In advance of the ring 30 I provide a space or cavityBla in which a medicinal preparation or tablet 32 is placed.

Upon the barrel, adjacent to the piston end, I arrange a front member33, which, like the piston, may be made of rubber and which includes aforwardly projecting tip 34. The front member includes an axial bore 35in which a needle 36, having a protuberance 3'I, is arranged. The needlecommunicates through a bore 38 with the interior of the barrel II.

Mounted upon the tip 34 is a closure 39, which includes a skirt 4Dengaging the tip, and a front end portion 4 I, which has a hole 42 toreceive and seal the pointed front end 43 of the needle 36.

The syringe is prepared, loaded and shipped in the condition shown inFig 2.

To prepare for injection the seal 2I is ruptured and the rear end memberI5 is pulled away from the barrel I I while the syringe is preferablyheld in a vertical position. This action lcauses a partial vacuum to beproduced in the forward end of the barrel, the pointed end 43 of theneedle fits in the hole 42. Liquid in the plunger is thus drawn throughthe bore 26 past the valve 2l and into the barrel through the space orcavity SIU.

3 so that any medicinal preparation in the cavity is subjected to thevehicle and is placed in solution, with the solution filling the forwardend of the barrel. During this operation the ball i? leaves its seat sothat air enters the bore i6 to bleed the interior of the plunger.

The movement is continued until the vehicle has been moved into thebarrel, whereupon the syringe is: ready for use as soonras the cap 39 isremoved. The injection is then made in the usual manner and the syringeis discarded.

In Fig. 4 I show a modification of my invention wherein similar partsare designated by single primed reference characters.

In the modification the piston 23' is extended so that it substantiallycovers the adjacent end of the plunger and is provided with a cavity 56in which a medicinal preparation 5l, similar to the preparation 32, maybe placed. The end of the plunger is provided with a valve seat 52 whichis engaged by a valve ball 53, arranged in a cavity 54 in the piston.The needle 36 includes an inwardly extending tube 55 which normallyengages the valve ball 53 and holds the latter on its seat so thatleakage is prevented during ship-` ment. In the modification theremaining' .parts are similar to those previously described and theoperation of the syringe is similar to that previously described.

In Fig. 5 I show a further modication wherein similar parts aredesignated by double primed' reference characters and wherein thepistonV 23" is provided with a cavity 60 which .may hold a medicinalpreparation 6l. The front of the piston 23 is provided with a cavity 62and with a self-closing hole 63- 'I'he piston being made of` softrubber, the partial vacuum produced in the barrel Il" causes the wallabout the hole 53 to be distended as the liquid in the plunger seeks tofill the partial Vacuum and thus the material is drawn from the plungerAand passes into the barrel where it dissolves the preparation 6|. InFig. 5 the needle terminates at the protuberance 31" and the needlecommunicates with the interior of the barrel through a bore 35, similarto the bore 38. The operation of the device shown in Fig. 5V is similarto that described above.

If desired, the tablet or drug may be omitted Vand a stock solution ofdrug and vehicle may be placed in the plunger. For some uses the bleedvalve at the rear end of the plunger may be omitted.

When the drug is present in the cavities 56 and 60, the piston, beingmade of soft material and. being held in forward position by the seal2l, the material of the piston about the cavities is sealed so that thedrug is secure in its cavity.

In the construction shown in Fig. 4, the cavity 54 in the the piston hasspaced ribs 56 therein, between which fluid in the tubular part i3'passes when the valve is opened.

The. subject matter disclosed in this application is similarv to thesubject matter disclosedy in my copcnding application Serial No.775,193, filed September 20, 1947 and is also similar to the subjectmatter disclosed in my other copending application Serial No. 775,192,filed September 20, 1947.

The present application discloses a construction similarl to theconstruction in the applicants copending application Serial Nos. 775,192and 775,193, both applications filed September 20, 1947. In the presentapplication, however, the claims are directed broadly and specificallyto a syringe wherein the piston plunger is provided with a valvepermitting the fluid to ow from a position in the rear of the pistonplunger to a position in front of the piston plunger. In applicationSerial No. 775,193 the claims are drawn `more cr less specifically tothe valved piston plunger and to the recess in the ampule front member,which recess is sealed by the piston plunger. In application Serial No.775,192 the claims are drawn to the front closure member and the needlecarrying cap thereon.

From the foregoing description it will be apparent that I have inventeda novel disposable hypodermic syringe which can be economicallymanufactured and which is highly eflicient for its intended use.

Having thus described my invention, I claim:

1. A syringe including a barrel, a plunger shiftable in said barrel,said plunger having a chamber therein, valve means arranged to permit owof fluid from the chamber into the front end of the barrel whilepreventing flow from the barrel into the chamber, there being a cavityopening into the forward portion of the barrel, means closing saidcavity when' the piston is in its forward position, a medicinalpreparation in said cavity and a vehiclefor thev preparation in thechamber, a needle, means to ii'xedly support the needle on the front endof the barrel, means to afford communication between the needle and theinterior of the barrel and removablev sealing means normally closingpassage through the needle. f

2. A syringe including a barrel, a plunger shiftable in said barrel,said plunger having a chamber therein, valve means on said plungerconstructed to permitV passage from 'the atmosphere into the chamber andpreventing passage therefrom, the front portion of said plungerincluding valve means arranged to permit flow of fluid from the chamberinto the front end of the barrel While preventing fiow into the chamber,there being a cavity opening into the barrel, a medicinal preparation insaid cavity and a vehicle for the preparation in the chamber, a needle,means to supportV the needle on the frontend of the barrel, means'toaiord communication be tween the needle and the interiorV of the barreland removable sealing means normally closing passage through the needle.

3. A syringe including a barrel, a plunger shiftable in said barrel,said plunger'havingr a cham-- ber therein, valve means constructed topermit passage from the atmosphere into` the chamber and preventingpassageV therefrom, valve means arranged to permit flow of fluid fromthe chamber into the front end of the barrel while preventing flow fromthe barrel into the chamber, there being a cavity opening into theforward portion of the barrel, means closing said cavity when the pistonis in its forward position, a medicinal preparation in said cavityv anda vehicle for theA preparation in the chamber, a needle, means to xedlysupport the needlev onthey front end of. the barrel, means tov aiordcommunicationv between the needle and the interior of the barrel andremovable sealing means normallyV closing passage through the needle.

4. A syringe including a barrel, a plunger shiftable in said barrel,said plunger havingv a chamber therein, a rear: end member on saidplunger,

said rear end member having a bore communi.

cating with the chamber, valve means in said bore constructed to permitpassage into the chamber and preventing passage therefrom,v the yfrontportion of said plunger including valve means arranged to permit flow ofiiuid from the chamber into the front end of the barrel while preventingiiow into the chamber, there being a cavity in said plunger in advanceof said valve means therein, a medicinal preparation in said cavity anda vehicle for the preparation in the chamber, a front member on saidbarrel, a needle on said iront member, means to afford communicationbetween the needle and the in.- terior of the barrel and removablesealing means normally closing passage through the needle.

5. A syringe including a barrel, a plunger shiftable in said barrel,said plunger having a charnber therein, the front portion of saidplunger including valve means arranged to permit flow of fluid from thechamber into the front end of the barrel while preventing ow into thechamber, there being a medicinal receiving, normally closed, pocketopening into the front end portion of the barrel, said pocket beingnormally closed when the piston is at the inner limit of its movement,means to releasably hold the piston at the inner limit of its movement,a medicinal preparation in said pocket and a vehicle for the preparationin the chamber, a needle, means to rigidly support the needle on thefront end of the barrel, and means to afford communication between theneedle and the interior of the barrel.

6. A syringe including a cylindrical barrel having an inwardly directedflange at one end, a plunger shiftable in said barrel, said plungercomprising a tubular body having an outwardly directed external flangeat one end, a rear end member engaging said external iiange and closingthe adjacent end of said tubular body, said rear end member having abore therethrough, a one-way valve in said bore, said valve beingconstructed to permit passage into the tubular body and preventingpassage therefrom, said tubular body having a piston thereon remote fromsaid rear end member, the front portion of said tubular body beingclosed and having a bore therethrough, a one-way valve in said lastmentioned bore, -said last mentioned valve being arranged to permit flowof fluid from the tubular body while preventing iiow into the tubularbody, there being a cavity in said tubular body bore in advance of saidvalve therein, a medicinal preparation in said cavity and a vehicle forthe preparation within the tubular body, a front member on said barrel,said front member having a bore, a, needle arranged in said front memberbore, means to afford communication between the needle and the interiorof the barrel and removable sealing means closing the outer end of theneedle.

7. A syringe including a cylindrical barrel, a plunger shiftable in saidbarrel, said plunger comprising a tubular body, a rear end memberclosing the rear end of said tubular body, said rear end member having abore therethrough, a one-way valve in said bore, said valve beingconstructed to. permit passage into the tubular body and preventingpassage therefrom, said tubular body yhaving a piston thereon remotefrom said rear end member, a closure for the front portion of saidtubular body, said closure having a bore, a valve seat in said bore, avalve on said seat, spring means normally urging the -valve to its seat,said valve being arranged to permit flow of fluid from the tubular bodywhile preventing flow into the tubular body, there being a cavity insaid tubular body bore in advance of said valve therein, a medicinalpreparation in said cavity and a vehicle for the preparation within thetubular body, a front member on said barrel, a needle on said frontmember, means to aiord communication between the needle and the interiorof the barrel and removable means to prevent outward flow through saidneedle and means closing passage through the needle.

8. A syringe including a cylindrical barrel, a plunger shiftable in saidbarrel, said plunger comprising a tubular body, a rear end memberclosing the rear end of said tubular body, said rear end member having abore therethrough, a one-way valve in said bore, said valve beingconstructed to permit passage into the tubular body and preventingpassage therefrom, said tubular body having a piston thereon remote fromsaid rear end member, the front portion of said tubular body beingclosed and having a bore therethrough, said last mentioned boreincluding a valve seat, a valve engaging said seat, said last mentionedvalve being arranged to permit flow of iiuid from the tubular body whilepreventing flow into the tubular body, there being a cavity in saidtubular body bore in advance of said valve therein, a. medicinalpreparation in said cavity and a vehicle for the preparation within thetubular body, a front member on said barrel, a

needle on said front member, said needle extending inwardly and engagingsaid last mentioned valve to hold the valve in its seat, and means toafford communication between the needle and the interior of the barrel.

9. A syringe including a cylindrical barrel, a. plunger shiftable insaid barrel, said plunger comprising a tubular body, a rear end memberclosing the rear end of said tubular body, said rear end member having abore therethrough, a oneway valve in said bore, said valve beingconstructed to permit passage into the tubular body and preventingpassage therefrom, said tubular body having a piston thereon remote fromsaid rear end member, the front portion of said tubular body beingclosed and having a bore therethrough, said piston being made offlexible material and having an end extending over the end of thetubular body, said piston end having a valve slit therein, said valveslit being arranged to permit iiow into the tubular body, there being acavity within the syringe and opening into the front end of the barrel,a medicinal preparation in said cavity and a Vehicle for the preparationwithin the tubular body, a front member on said barrel, a needle on saidfront member, means to afford communication between the needle and theinterior of the barrel and means closing passage through the needle.

10. A syringe including a barrel member, a hollow plunger shiftable insaid barrel member, a medicinal preparation in one end portion of thebarrel member, valve means arranged to permit iiow of iluid from one endportion of the plunger into said one endportion of the barrel memberwhile preventing return flow into the plunger, a vehicle in the hollowplunger, a needle, means to support the needle, and means to affordcommunication between the needle and the interior of the barrel member.

11. A syringe including a barrel, a plunger shiftable in said barrel,said plunger comprising a tubular body, valve means arranged to permitflow of fluid from the tubular body into the front end portion of thebarrel while preventing return iiow into the tubular body, a medicinalpreparation in the forward portion of the barrel, a vehicle within thetubular body, and a needle on said barrel and communicating with theinterior of the barrel.

anemona 125. Az syringe includln a; barrelvmember, a- `Hollow plungermember shiftable in said barrel member;l a medicinalpreparation in oneend por@ tion of the learrei-v member,v4 a; valve meansarrangedt'opermit ow of Huid, from one `end portionofAV the plunger intosaid one end portion of the barrel member while preventing return 110Winto: the plunger mem-ber; meansto bleed the other end portionr of theplunger to the atmosphere, a vehicleI in the hollow plunger, a needle,meanstosupport the needle on the syringe and meansV to` aiordcommunication between the needlev arid.` the interior of. the barrelmember;

13. A syringe including avv barrel, a plunger shiftabie in said; barreLsaid: plunger comprising a tubular body, means'- closing the rear end ofsaid ubuiar body, said rear end.- closng means Having a bore, acne-wayvalve in said bore, said val-ve being constructed tol permit passageinto the tubular body and preventing. passage therefrom, valve meansarranged to permit owof..-

REFERENCES CITED Thel following references are of' record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date,

1,241,352 Doering 'Sept. 25191175 1,594,493 Brown Aug. 3;. 19261l1,607,271 Smith Nov..16, 1926 11,909,591 Nevin May 1.6,v 1933

